In the case where a conductive pattern (a wiring pattern) is formed on a substrate such as a printed board, photolithography and etching are performed in general, and since these processes include a large number of complicated procedures, time and labor are necessary for forming a conductive pattern in general.
As a technique to form a fine conductive pattern without performing such processes, a method in which a conductive pattern is drawn on a substrate by using a conductive paste including metal nano-particles and the thus obtained conductive paste layer is heated for forming a desired conductive pattern is known (for example, Patent Documents 1, 2 and the like).
As a general method for drawing a conductive pattern, a screen mask provided with an opening is used as a template for applying a conductive paste in a desired thickness by a screen printing method (for example, Patent Document 1 and the like). Apart from this, a method in which a conductive paste is directly sprayed by an inkjet method for drawing a desired conductive pattern has been developed (for example, Patent Document 2 and the like).
Patent Document 1: Japanese Laid-Open Patent Publication No. 2004-247572
Patent Document 2: Japanese Laid-Open Patent Publication No. 2002-134878